UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 27, 2004 IRON MOUNTAIN INCORPORATED (Exact name of registrant as specified in its charter) PENNSYLVANIA (State or other jurisdiction of incorporation) 1-13045 23-2588479 (Commission File Number) (IRS Employer Identification No.) 745 Atlantic Avenue Boston, Massachusetts 02111 (Address of principal executive offices, including zip code) (617) 535-4766 (Registrant's telephone number, including area code) Item 5. Other Events. On May 27, 2004, Iron Mountain Incorporated (the "Company") announced the authorization and approval of a three-for-two stock split effected in the form of a dividend on the Company's Common Stock, par value $0.01 per share. Shares of the Common Stock will be issued on June 30, 2004, to all stockholders of record as of the close of business on June 15, 2004. For more information, see the Company's press release, dated May 27, 2004, which is attached herewith as Exhibit 99 Item 7. Financial Information and Exhibits. (c) Exhibits. EXHIBIT NO. ITEM 99 Press release dated May 27, 2004. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. IRON MOUNTAIN INCORPORATED (Registrant) By: /s/ Jean A. Bua -------------------------- Name: Jean A. Bua Title: Vice President and Corporate Controller Date: May 27, 2004